128505961664 has 28 divisors (see below), whose sum is σ = 255183400224. Its totient is φ = 64207782144.

The previous prime is 128505961657. The next prime is 128505961667. The reversal of 128505961664 is 466169505821.

It is not an unprimeable number, because it can be changed into a prime (128505961667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 614447 + ... + 796590.

Almost surely, 2^128505961664 is an apocalyptic number.

It is an amenable number.

128505961664 is a deficient number, since it is larger than the sum of its proper divisors (126677438560).

128505961664 is a wasteful number, since it uses less digits than its factorization.

128505961664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412472 (or 1412462 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 53.

The spelling of 128505961664 in words is "one hundred twenty-eight billion, five hundred five million, nine hundred sixty-one thousand, six hundred sixty-four".